Standard image viewing on computer displays (e.g., web browsers and other software applications) is generally achieved by implementing of set of fixed zoom levels that can either be selected directly (see e.g.: MapQuest at www.mapquest.com) or that are addressed sequentially. The problem with the preset zoom levels is that several user interactions might be required, each of which having a time lag due to transmission and a cost disadvantage due to multiple transmissions from the server to the computing workstation. Any preset zoom level will be wrong in a large number of cases. For example, the zoom level needed to read the headline of a newspaper article is different from the zoom level required to read the body of the article. It would thus be desirable that the zoom level is automatically selected, based upon the image area the user selects or is interested in viewing. It should be noted that every new image displayed by the client (workstation or computing device) is the response from a server request, that is for any zoom change or location change, a new server request is generated and the new image is transmitted to the client. Moreover, even on relatively large displays, user dissatisfaction is caused by every “useless” selection (e.g., click) the user has to make.
Textual documents are often considered “text only” meaning that all information is encapsulated in the ASCII text. In reality, a large amount of information is encapsulated in the spatial structure of the text. Moreover, documents are “best” used when the display of the documents directly reflects the intended document layout—where the zoom or magnification level is adapted to the document being viewed. In light of the potential delay or cost of retransmitting data for display, getting the display “right” is important.
Adaptive zooming has been used in cartography and computer graphics applications, as described, for example, by several researchers, including Alesandro Cecconi, et al., James D. Hollan, and Bernhard Preim et al. Documents can be viewed in either their ASCII form (if available) or in an image form, showing the spatial layout. When displaying the image of a page on small display, it is generally the case that no text can be read. Accordingly, the disclosed system and method include a locally adaptive zoom for the display that will-on user request-zoom the indicated region as a function of the local document content. The local content will be derived by image analysis of the user selected image part. In contrast to higher level document information, such as disclosed in the cross-referenced applications above, an examination of the actual raster is performed. This method is applicable to native raster documents (scans) and rendered pages.
A problem with viewing documents is the trade-off between readability of local document areas and the overall “view” of the document. The current solution to this problem is to scroll and zoom (i.e.: the user zooms to a higher magnification to read or view detail and then and scrolls if necessary). One significant problem with such functionality is that the “next” zoom level is not generally adapted to the document and is, therefore, often not adequate to read or accurately perceive the document. This leads to a high level of user dissatisfaction, particularly in situations that have a time lag or cost associated with each new view, as is the case in portable display devices (e.g., mobile/cellular telephones, personal digital assistant devices (PDAs), etc.), including Xerox'mDoc™ software enabled platforms.
For example, the phrase “Company Confidential” has a very different meaning when appearing at the top of a page than a meaning when appearing in the middle of a paragraph on that page. Consequently, textual documents are often viewed in spatial layout or image mode showing the spatial relationship of all parts. Quite often, when viewing textual documents, the full image view is used to identify an area of interest. For example, the e-mail address will be somewhere in the address block, the “total cost” will be somewhere near the bottom of the spreadsheet, etc. In such cases, image view effectuates a quicker identification of the proper location on the page. When displaying an image of a page on a small display screen a user thereof may often find it difficult to read the small text, if it can be read at all. Subsequently, the user indicates the zoom function and the image view changes the zoom in a preset fashion. However, jumping between zoom levels is also potentially time consuming and costly, leading to a need to dynamically determine an appropriate zoom level—as a function of both the image detail and the display resolution of the viewing screen.
A patent document 110, as illustrated in FIG. 1, shows the general layout of the document but text portions 120 thereon are unreadable. Anybody familiar with the general layout of patent documents can identify different regions thereof such as, Patent Number, Issue Date, Author, Application Date, References Cited, etc., without actually being able to read the words. In this case, structural information of the document is sufficient for the user to identify a particular region of interest to zoom in on.
Preset zooming capability may also assist the user in this regard. For example, upon each user request, a click of a special key, the server will provide an enlarged image of the selected region of the document at the next zoom level. One problem, however, with a preset zoom is that several interactions might be required to get it right, with each interaction involving a time lag due to transmission between the document server and the user's display device or due to multiple transmissions having to occur. In addition, any preset zoom level may be incorrect in a number of instances. For example, the zoom level needed to read an e-mail address in a Microsoft Word® document would most likely be different from the zoom level to read a sales number in a Microsoft PowerPoint® document. It would thus be desirable that the zoom level be automatically selected based on various image areas on which the user can click or otherwise select.
In document server, image viewer implementations, zooming results in the display of the “next” preset zoom level, for example as indicated by display image 210 in FIG. 2. Moreover, FIG. 3 illustrates, in display image 310, a zoom level needed to read the Patent Number and Date of Patent from FIG. 1 within a display window 320. Still, the Reference Cited section is not readable and the patent number is barely, if at all readable. FIG. 4 depicts the References Cited section at the identical zoom level as the one in FIG. 3. It will take the user several more “clicks” or zoom adjustments, with the corresponding latency for transmission, to be able to retrieve the desired information. As can be seen from FIG. 4, more user “clicks” are required to reach the readability of FIG. 5.
As illustrated in the examples, a large number of user zoom adjustments are required to retrieve the desired information. The exact number of adjustments depends on the size of the actual font, the zoom level increments that are encoded into the system, as well as the relative locations of the different areas. For the example given, the total number of selections will be in the order of twelve or more in order to view various portions of the patent page. It is, therefore, an aspect of the disclosed system and method to reduce the number of zoom adjustments and/or scrolling (i.e., user interventions) that are required to display desired regions of an image.
What is required is a system or method to incorporate a locally adaptive (i.e., dynamic) zoom adjustment capability into any display screen such that a zoom of an indicated region is a function of the local document content derived from the higher level document description (font size, raster resolution, etc.) contained as source information inside the original source document. Although the present description is being presented in the context of wireless transmission, it should be noted that the dynamic zoom is desirable in most embodiments where there is latency between the user request and the server response, as well as in cases, where the amount of required user interaction is intended to be reduced. Thus, even on a local computer or other workstation, it would be desirable to have a dynamic zoom that automatically adjusts the zoom ratio to the detail in the user indicated area without mandating multiple user interactions. Accordingly, as used herein, terms like “server” or “display” are intended to designate functionality, but not necessarily indicate or be limited to a particular hardware or software embodiment as described.
A method is disclosed for selecting the zoom factor when inspecting a region of a document on a soft display based on knowledge of information depicted in the region. For example, the type or font size in the region selected such that the text is “just readable,” or dependent upon raster data in the user selected local area. It is understood that the output system resolution influences the “just readable” criterion and that the calculated zoom factor is a function of source size information as well as output or display capabilities.
Disclosed in embodiments herein is a method for providing a source document for display, comprising: identifying a plurality of sections of the source document, and at least one characteristic of each section; associating a display zoom factor with each identified section based upon the at least one characteristic of each section; creating an adjusted zoom image of at least a selected section in response to the zoom factor; and sending the adjusted zoom image of the selected section for display.
Also disclosed in embodiments herein is a document display system, comprising: a source document image created from a rasterized image; a server for processing the source document image and identifying a plurality of sections of the source document, and at least one characteristic of each section; and a computing device, including a display associated therewith, for displaying at least a section of the source document, wherein the section is displayed as an image received from the server, and where the image is created using a zoom factor based upon the at least one characteristic of the section.
Further disclosed in embodiments herein is a method for providing a source document for display on a handheld device, comprising: Identifying, with a server, a plurality of sections of the source document and for each section determining at least one characteristic representative of said section; for each identified section, associating at least one zoom factor therewith based on the at least one characteristic representative of said section; sending a first document image, at a first zoom level, from the server to a handheld device for display thereon; selecting, using the handheld device, a section of said document for zooming; transmitting, from said handheld device to the server, information identifying the selected section; creating on the server, in response to the information identifying the selected section, a second document image including at least a portion of the selected section at a second zoom level; and sending the second document image from the server to the handheld device.